Other Respects on SBLI Controls
Pp. 263-287 (25)
Chaoqun Liu, Qin Li, Yonghua Yan, Yong Yang, Guang Yang and Xiangrui Dong
An implicit Large Eddy Simulation (ILES) is carried out for a Micro Vortex
Generator (MVG) controlled supersonic ramp flow at Ma = 2.5 and Re = 5760 based
on inflow momentum boundary thickness. The results are validated against the TU
Delft experiment on the same MVG geometry and Mach number. Several techniques
are used to analyze the coherent structures in the MVG wake. The vortex system in the
MVG wake is visualized using vortex identification method and it is found that two
primary counter rotating streamwise vortex pair are induced by the MVG, which would
further lead to a trail of vortex rings through K-H instability. The average distance
between adjacent vortex rings is determined by a spatial auto-correlation of vorticity,
which is estimated as 1.5 MVG height. Two dimensionality reduction algorithms,
namely Proper Orthogonal Decomposition (POD), and Dynamic Mode Decomposition
(DMD) are applied to a set of flow field sequences on the spanwise symmetry plane.
POD modes identify structures containing most of the turbulent kinetic energy and
DMD modes, capturing single frequency structures which are most essential to the
Dynamic Mode Decomposition (DMD), Modes Analysis, MVG,
Proper Orthogonal Decomposition (POD).
Center for Numerical Simulation and Modeling, Department of Mathematics, University of Texas at Arlington, Arlington, Texas 76019, TX, USA.